Question about white spots on tomato leaves

Asked August 9, 2015, 1:51 PM EDT

In the last few days I noticed that my tomato leaves are getting white patches on them. Also, the leaves are a lighter green than they were earlier. The fruit is fine and new tomatoes continue to form. I have not used chemical fertilizers or pesticides. I water the plants at their base once a week. They get a lot of sunlight, but are not in full sun. Please let me know if this is a harmful condition. If it is harmful, what is it and what can I do to stop the formation of these white patches? Thanks a lot.

Montgomery County Maryland

1 Response

Usually white patches are sunscald and associated with overhead watering, or fertilizer or pesticide burn. It would be helpful if you could send us photos.

It may have to do with watering. Watering cannot be done on a schedule, unfortunately. As the plants grow, they require more water. Higher temperatures, more sun, and breezes will all cause water loss. The only foolproof way to water is to poke a finger in the soil and water when the soil dries down below about 1". Then soak the soil thoroughly. A mature tomato plant can require several gallons of water a week in the summer.